On the role of stress waves in dynamic rupture of cylindrical tubes

Abstract

A systematic experimental/computational study was performed to investigate the role of stress waves in ductile fracture of cylindrical tubes. The stress waves were created by high‐speed moving load, which was produced by detonation of explosive cord inside two intact and two pre‐flawed steel tubes. Several distinct phenomena like cyclic crack growths in Modes I and III, crack flap bulging and crack curving/branching were observed and simulated by finite element (FE) method. The FE models were composed of 3D brick elements equipped with interface cohesive elements. The analysis results showed that the crack growths in Modes I and III were governed by the detonation‐induced stress waves. The crack speeds were obtained based on the increments of cyclic crack growth and the time period of the stress waves. The estimated crack speed range was 63–230 m s−1 for the axial growth, whereas the average speed for growth in Mode III was 100 m s−1.

Deformation and fracture of cylindrical tubes under detonation loading: A review of numerical and experimental analyses

“…Due to symmetry, if the energy release rate of the crack is high enough to support two crack fronts, then branching at this point is also possible. This effect was presented with both experimental and numerical results by Mirzaei et al [136] (Figure 16).…”

“…Malekan [135] investigated crack propagation in a tube under internal detonation using cohesive elements and compared their experimental results with literature values. Mirzaei et al [136] investigated the role of stress waves in the ductile fracture of cylindrical tubes using a combination of computational and experimental analyses. Meanwhile, Malekan & Cimini [137] numerically modeled the effect of composite patches made of either glass or boron/epoxy on the response of a tube fractured under an internal dynamic moving load and more recently, Eskandari [138] described the linear elastic response of a cracked tube coated with a functionally graded material (FGM) and subjected to a detonation load.…”

On the vibrational responses of thin FGM tubes subjected to internal sequential moving pressure

“…Abaqus ® calls these subroutines at all integration points of the elements that have material properties defined using the field variables [21]. Loading properties are set similar to those presented in [7,13,52] and are shown in Table 1. There are five load types for this investigation depending on the detonation speeds: 1400.1, 1478.8, 1699.7, 2500, and 7040 m/s.…”